The prior art already includes a number of different movable floor systems for swimming pools which allow a water-filled cavity functioning as a swimming pool to be transformed into a flat surface able to take traffic. Thus, there exist notably platforms which can be moved from a low position, in which they form the floor of the swimming pool, to a high position, in which they form a walk-on floor, or from the high position to the low position. Some platforms can also be at intermediate level as a means of adjusting the depth of the swimming pool for special uses.
However, the existing systems have certain drawbacks.
In the first place, the manufacture of the platforms is complicated and expensive because of the large number of different parts that have to be assembled. These platforms usually consist, notably, of a mesh, in most cases of metal, made up of long parallel longitudinal bars, with short transverse elements having to be fixed between two consecutive longitudinal bars. Consequently the number of transverse elements is very large, hence requiring time and adding to the complexity of producing such a mesh.
In the second place it is often desirable to connect the platform to a pulling and/or pushing system to raise or lower the surface which can thus act alternately as the floor of the swimming pool or as a walk-on floor. A pushing or pulling system of this kind is usually voluminous, and its installation at the bottom of the swimming pool makes for a not-insignificant loss of volume of the part of the cavity that can actually be used as a swimming pool.
Besides this, there are devices described notably in U.S. Pat. No. 2,823,239 providing a structure comprising a platform made up of parallel beams and parallel crossmembers allowing a movable swimming pool floor to be raised and lowered. However, such a device has the drawback of being heavy and requiring a large amount of energy to raise it. Another drawback is its structure, comprising two superimposed layers, making it voluminous, cumbersome and expensive.